The present invention is directed to a dental spray handpiece having an elongated nozzle with a discharge orifice through which air, water or a mixture thereof is sprayed. The dental handpiece has a housing forming a grip or grasping member which at one end is connected to a supply hose and has the other end connected to the nozzle by a rotating joint which allows disassembly. The handpiece also includes an arrangement for conducting light from a source to a point adjacent the discharge orifice where the light is projected in the direction of the spray discharge.
Spray handpieces or dental syringes which have a nozzle connected to a housing and are provided with a valve arrangement to enable either discharging air or water or a mixture of the two, are known. An example of the handpiece is disclosed in U.S. Pat. No. 4,149,315.
In order to have a better view of the work area in the region of the oral cavity when using a spray handpiece having a spray nozzle part, it has been necessary up to now to provide an additional handpiece with an illuminating means, for example, in the form of a light waveguide handpiece which is known, for instance, from U.S. Pat. No. 3,614,415. Certain locations in the oral cavity, either cannot be illuminated or cannot be satisfactorily illuminated with normal work area lamps because heavy shadows will occur under certain conditions at the immediate treatment location when working with the instrument or because the light intensity is inadequate for adequately illuminating the oral cavity. These locations can be optimally illuminated with such a punctiform illumination device as disclosed in the above patent.
A dental handpiece equipped with an illumination device is disclosed in U.S. Pat. No. 2,522,261. This handpiece indeed is designed for the emission of water and air but is principally designed for sucking fluid out of the oral cavity of the patient. Accordingly, the handpiece essentially consists of a central suction tube leading up to the suction mouthpiece which is connected to a handle portion by an angled tube portion so that the arrangement has a hook or U-shaped configuration. The delivery of air and water will occur by means of feed lines which are secured to the outside of this suction tube.
The illumination means, which consist of a lamp is disposed at a horizontal part on the inside of the angled suction tube, which is connected to the evacuation means. The lamp is supplied with voltage by means of electrical lines conducted in the suction channel or tube and is interchangeably mounted in a correspondingly designed mount. The evacuation handpiece can be pivoted toward both sides together with the lamp and the ends of the agent lines. The disadvantage is that the agent lines including those on the outside of the tube are twisted on their axes during this pivoting of the mouthpiece of the handpiece and the cross-section is thus constricted with the agent delivery being thereby interrupted under certain conditions.